What is a Case Report?
High-quality case reports “make explicit … why an observation is important in the context of existing knowledge. They have a high sensitivity for detecting novelty and are a cornerstone of medical progress…” [Vandenbroucke 2001]
A case report tells a compelling story with data that describes a patient’s episode of care for scientific or educational purposes. [Riley 2017] Case reports provide early signals of potential benefits, harms, and cost. Collecting and analyzing this data provides insights into what works, for which patients, and under which circumstances.
Effectiveness versus Efficacy
Effectiveness evaluates the outcomes from a real-world clinical setting that are described in a case report. In contrast, clinical trials provide evidence of efficacy — outcomes in the controlled setting of a clinical trial. Clinical expertise relies on information on efficacy and effectiveness. Accurate effectiveness information from clinical practice generates testable hypotheses for clinical research and feedback on clinical practice guidelines.
Beneficial and Adverse Effects
Historically, case reports have helped identify adverse and beneficial effects, the recognition of new or rare diseases, and unusual presentations of even common illnesses. Two examples include the association between the prescription of thalidomide to pregnant women and congenital abnormalities in newborn infants [McBride 1961] and the use of propranolol for the treatment of infantile hemangiomas [Levy 2012]. The publication of case reports in indexed medical journals continues to grow, increasing by 45% from almost 50,000 in 2000 to more than 70,000 in 2010 on EMBASE and MEDLINE alone. [Sun 2013]
Case Reports Challenges
Causal inferences are difficult to establish from single cases, and when written without guidance from reporting standards, case reports may be inconsistent and insufficiently rigorous. [Kaskin-Bettag 2012] A study of more than one thousand case reports from four peer-reviewed emergency medicine journals found that more than half failed to provide information related to the primary treatment that would have increased transparency and replication. [Richason 2009]
Guidelines and Checklists as a Solution
The CARE Guidelines for case reports were developed by an international group of experts following the recommendations from the “Guidance for Developers of Health Research Reporting Guidelines”. [Moher 2010] These guidelines were created to increase the accuracy, usefulness, and transparency of case reports. Since publication of articles in the Journal of Clinical Epidemiology (2013 and 2017) by the CARE group, the CARE guidelines have been endorsed by multiple medical journals and translated into more than ten languages. The CARE guidelines support the Equator Network’s efforts to improve the transparency and accuracy of health research reporting.
Benefits for healthcare stakeholders when case reports are written following the CARE guidelines include:
Patients receive accurate information on therapeutic options.
Clinicians improve clinical reasoning and peer-to-peer communication.
Researchers access hypotheses coming from real-world clinical settings.
Medical education receives support for case-based learning.
Policy makers gain feedback on effectiveness in clinical practice and CPGs.
Medical journal editors and peer reviewers have tools for evaluating case reports.
Evidence-based medicine is commonly portrayed using a pyramid with efficacy increasing as one moves UP the pyramid. Reporting guidelines are in place for many study designs and have increased the usefulness of data used to inform the creation of clinical practice guidelines (CPGs). These range from CARE for case reports [Gagnier 2013] to STROBE for observational studies [von Elm 2007], CONSORT for randomized controlled trials [Schulz 2010], and PRISMA for systematic reviews and meta-analyses [Moher 2012].
Case reports offer feedback from clinical practice that may prove useful in the creation and evaluation of clinical practice guidelines.
Benefits of Case Reports following CARE
Creating a high-quality, useful case report that is accurate AND transparent can be more challenging than it first appears. Training in case report writing makes the process more efficient and publication in a medical journal more likely. The CARE guidelines are useful for diverse specialties and therapeutic interventions, from surgery, to radiology, to acupuncture and to nursing. We have been teaching case report writing following the CARE guidelines since their publication.
Everyone benefits when healthcare data is systematically collected and transparently reported. High-quality case reports following the CARE guidelines offer an opportunity for a diverse group of healthcare stakeholders to communicate, collaborate and advance the state of healthcare around the world. Vandenbroucke put it best when he stated, “Case reports… are a cornerstone of medical progress.” [Vandenbroucke 2001]